Nvim hangs while editing JavaScript object literals in an HTML file after first opening a JavaScript file

[darthmall]

This is a little bizarre, so bear with me. If I try to insert a JavaScript object inside another JavaScript object in a script tag in an HTML file after having opened another JavaScript file first, nvim will hang. I can see in top that its CPU usage spins up to 100%. The steps below will probably make this more clear.

• nvim --version: 0.3.1
• Vim (version: 8.0) behaves differently? Yes, I wasn't able to reproduce this in Vim8
• Operating system/version: Ubuntu 18.04
• Terminal name/version: GNOME Terminal 3.28.2
• $TERM: xterm-256color and screen-256color

Steps to reproduce using nvim -u NORC

1. nvim -u NORC foo.js
2. :vs index.html
3. Add the following lines to index.html

<script>
  var x = {
  }
</script>

4. Insert a property y: {} into the object x

 <script>
   var x = {
+    y: {
+    }
   }
 </script>

Actual behaviour

As soon as you hit enter after the opening { in y: {, nvim becomes unresponsive.

This only happens if you have opened another JavaScript file first. If you nvim -u NORC index.html and then :vs foo.js and add the same HTML to index.html, it works fine. Also, if you insert the } before you insert the {, it works fine.

And if you start nvim with -u NONE instead of NORC, it works.

Expected behaviour

Nvim should continue to function normally after typing y: {\n.

Updated 21 Nov. 2018 16:42 -0700 to correct the steps to reproduce, see my comment below.

[mhinz]

FWIW, I can't reproduce it with 0.3.1 from Homebrew, but since it happens on an opening bracket, it might be related to the standard plugin matchparen (:h matchparen).

Does executing :NoMatchParen before adding the y: {} line avoid the issue?

[darthmall]

I just realized there was a subtle error in how I described reproducing the bug. It's not entering the { that causes nvim to hang, it's hitting enter after the {. So the lines you're actually adding are:

 <script>
   var x = {
+    y: {
+    }
   }
 </script>

So really this has something to do with inserting a new line after the {. I can enter y: {} just fine, but as soon as I try to add a newline in between the {} it crashes.

Setting :NoMatchParen doesn't change anything for me.

[mhinz]

Ah, there you go. I can reproduce it like that. (You can break it via <c-c>.)

I wasn't closely following recent changes, but I can confirm that it's fixed on master and will work in the next release.

[justinmk]

We are up-to-date with Vim's runtime changes, so that explains why it's fixed on master.